It's the picture above your name (you have the pink bobbly people at the moment, you have an anonymous avatar).
You put this in gardening by the way - thought perhaps Avatar was a new dahlia name....
Technically it is a manifestation of a deity or other divine power that is assumed by a mortal either to guide them in an aspect of their life or to give them additional powers in battle.....
Hi oxo....Whilst rowanwitch has given a literal meaning for Avatar, I feel you should take note of what boxtops has said and if you would like to change your bobbly people to what is known as an Avatar in answerbank, then click the following:-
Agree with you there Rowan.......think it's from Hinduism and as you say a manifestation of a Deity
Websites could have thought of a better word to use